Highlight a variable between C and Labview?

Question

What is the best way to allow C code to regularly receive the instantaneous value of an integer generated from a separate Labview program?

I have a time-critical C code that controls a scientific experiment and records data every 20 ms. I also have some labview code that controls another tool and prints an integer value in 100 ms. I want my C code to be able to write a value from labview. What is the best way to do this?

One idea is for Labview to write an integer to a file in a loop and have C code that reads the value of the file in a loop. (If necessary, I could add a second thread to my C code.) Labview can also reference the C dll. Therefore, I could write a DLL in C, which somehow facilitates the sharing of the two programs. Is it appropriate? How should I do it?

Answer 1

I followed one of @stijn's ideals:

there is a C application, and the other dll is shared memory. LV will load this DLL and call the method on it to write the value to the shared memory, then application C will be able to read it after polling the flag (which needs a lock!).

I wrote the InterProcess library available here: http://github.com/samuellab/InterProcess

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Answer 2

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Answer 3

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